An argument can be logically valid, but unsound in that it contains a false premise and, therefore, leads to a false conclusion (e.g., Scientists are smart; smart people do not make mistakes; therefore, scientists do not make mistakes).

Norway, Iceland, Australia, Canada, Sweden, Switzerland, Belgium, Japan, the Netherlands, Denmark, and the United Kingdom are among the least religious societies on earth. According to the United Nations' Human Development Report (2005), they are also the healthiest, as indicated by life expectancy, adult literacy, per capita income, educational attainment, gender equality, homicide rate, and infant mortality. . . . Conversely, the fifty nations now ranked lowest in terms of the United Nations' human development index are unwaveringly religious.

Nothing guarantees that reasonable people will agree about everything, of course, but the unreasonable are certain to be divided by their dogmas. It is time we recognized that this spirit of mutual inquiry, which is the foundation of all real science, is the very antithesis of religious faith.

The perpetrators of the Inquisition - the torturers, informers, and those who commanded their actions - were ecclesiastics of one rank or another. They were men of God - popes, bishops, friars, and priests.

It is merely an accident of history that it is considered normal in our society to believe that the Creator of the universe can hear your thoughts while it is demonstrative of mental illness to believe that he is communicating with you by having the rain tap in Morse code on your bedroom window.

While religious tolerance is surely better than religious war, tolerance is not without its liabilities. Our fear of provoking religious hatred has rendered us incapable of criticizing ideas that are now patently absurd and increasingly maladaptive.

It is still fashionable to believe that how you organize yourself religiously in this life may matter for eternity. Unless we can erode the prestige of that kind of thinking, we're not going to be able to undermine these divisions in our world.